Molded pulp egg carton



May 25 1955 R. F. RElFERs ETAL. 3,185,370

MOLDED PULP EGG CARTON original Filed oct. 5, 1959 esmas-sheer, 1

INVENTORS Rlchard E Reifers Henry A. Lord ATTORNEY May 25, 1965 R. F.REIFERS ETAL 3,185,370

MOLDED PULP EGG CARTON original Filed oct. 5. 1959 e Sheets-sheet 2FIGA - 1NVE1-rroRS Richard E Refers 8 Henry A. Lord BY Mez. 0, 7/.acw

ATTORNEY May 25, 1955 R. F. REU-'ERS ETAL 3,185,370

MOLDED PULP EGG CARTON Original Filed Oct. 5, 1959 8 Sheets-Sheet 3INVENT ORS Richard E Refers Henry A. Lord Y BY MPL d 7-2ocA/s W ATTORNEYMay 25, 1955 R. F. REU-ERS ETAL 3,185,370

MOLDED PULP EGG CARTON Crgnal Filed Oct. 5, 1959 8 Sheets-Sheet 4mvENroRs Richard F. Reifers8= Henry A. Lord BY Maw @Igea/YS' ATTORNEYMay 25 1965 R. F. RElFERs ETAL 3,185,370

MOLDED PULP EGG CARTON Original Filed Oct. 5, 1959 8 Sheets-Sheet 5 INVENT ORS Richard E Reifers Hen ry A. Lord ATTORNEY May 25, 1955 R. F.RElFERs ETAL 3,185,370

MOLDED PULP EGG CARTON Original Filed Oct. 5, 1959 8 Sheets-Sheet 6nvwsNroRs` Richard F. Reifers 8 Henry A. Lord ATTORNEY May 25, 1955 R.F. REIFERS ETAL 3,185,370

MOLDED PULP EGG CARTON Crginal Filed Oct. 5, 1959 8 Sheets-Sheet '7 INVENT ORS Richard E Refers 8- ATTORNEY R. F. REIFERS ETAL 3,185,370

May 25, 1965 MOLDED PULP EGG CARTON 8 Sheets-Sheet 8 Original Filed Oct.5. 1959 .www

Nl' Y rill 1NvENToR Richard F. Reifers Henry A. Lord BY /IRL Ecc/(sATTORNEY United States Patent C) 3,185,370 MOLDED PULP EGG CARTN RichardF. Reifers, New Canaan, Conn., and Henry A.

Lord, Palmer, Mass., assignors to Diamond International Corporation, acorporation of Delaware Original application Oct. 5, 1959, Ser. No.844,438.

Divided and this application Oct. 1S, 1962, Se

4 Ciaims. (Cl. 229-25) The present invention relates to an egg carton orsimilar article made of molded pulp.

This application is a division of applicants `co-pending applicationSerial No. 844,438 tiled October 5, 1959, now abandoned.

In the art of making articles of molded pulp, there are three well-knownprocesses.

In the first process, the article is formed by being molded onto a moldthat has suction applied to one side thereof and is immersed in a slurrythat is made up of wood and/ or paper fibers and water, the bers lbeingsucked up by the suction applied to the mold and held by a screenthereon that is in the shape of the article to be made; the water passesthrough the screen and is exhausted. From the mold, the article istransferred in the first process to a support that is generally planarand passes through a heating means, such as an oven. This -is known asfree drying. Where a higher quality product is desired, the free-driedarticles may be hot pressed between mating pressing dies, and this mayor may not be accompanied by a spraying of the article.

In a second well-known process, the article is molded or formed as abovestated, but is transferred after being molded on-to a form and it is onthis form that it passes through the oven or other heating means; theform may or may not be heated itself either in addition to or as -asubstitute for the oven type heating means. After the drying step, thearticle is transferred to mat-ing pressing dies as above described. Thisprocess is known as the form drying process.

In the third process, two articles are formed on separate molds andthese articles are then brought together and laminated, so that theresul-tant article is laminated from the two molded articles. ln thisprocess, in which 'form drying is preferably used, the composite o1'laminated article is pressed between male and female heated dies.

It is understood in the Iart `that free drying gives the most warpage,that form drying considerably reduces the warpage and that hot pressingsubstantially eliminates all warpage and restores the article to theform and shape that it had when originally molded.

In all of these processes, and in variations of them known to the art,the after-pressing, which is lthe pressing that takes place after themolding or forming of the article, is -for the purpose of restoring thearticles shape to that it originally had and hence was recognized as acorrecting or reotifying step in wh-ich little or no changeV was made inthe actual coniiguration of the article, such changes as were made beinglargely for producing only surface effects on the articles.

In addition to these three generally recognized processes, there is alsoknown a process in which the initial molding operation is of a sheettha-t is thereafter formed into the desired configuration by pressingthe article to the desired form. This is similar to the well-known pressforming of sheet metal, and is limited as to depth of draw of thearticle and to simple geome-tric shapes.

One of the prim-ary uses of the articles produced .from molded pulp 4isfor the packaging of fragile articles, egg cartons being one leadingexample. There are certain 3,i85,370 Patented May 25, 1965 ICCcharacteristics that are desired for the egg cartons that are produced,and some of these characteristics, at least, depend upon the process bywhich the article was made. For example, in cartons for packaging eggs,it is desirable to have a carton that is strong and will withstand acon- Sider-able amount of force. This is necessary in order that thecarton may be handled in automatic machinery and may protect the eggs,or other fragile articles, from shock and other forces that arise duringthe handling of the lilled carton both in automa-tic closing and sealingmachinery and in Ithe transporting of the lled carton from piace toplace during the marketing operations, In addition to the strengthcharacteristics, the carton must not be hard and unyielding for if itwere, the eggs would be subjected to impact shocks that would tend tocause egg breakage. Consequently, it is desirable that those parts ofthe carton that are in contact with the egg or other fragile objectpossess a certain amount of softness and/or resiliency so that `theshocks will be cushioned and their effect mitigated to thus reduce oravoid egg breakage. In particular, -i-t has been found that articlesthat are yafter-pressed, that is, that are pressed after the molding anddrying operations, have imparted to them a reduced hardness and a smoothsurface. This is due to the fact that the fibers are disturbed fromtheir original bond by the pressing along with the reduction of originalthickness.

Because after-pressing was known to reduce hardness of the carton, manyworkers in the art have previously sought to provide a configuration ofcarton that would take advantage of this result. For example, there areknown in the prior art egg cartons in which the egg cells have convexribs that extend into the concave cells and are engaged by an egg placedtherein. It has even been stated in the prior art that these rib-s orflutes will deiiect, as when a large egg is placed in the cell; however,this deflection is of a rib or flute that is molded into the carton andythus partakes of the known strength of the carton material plus addedrigidity because of its shape. Consequently, experience has shown thatthese tintes or ribs do not readily deect and consequently there is lessdetiection and cushioning than Was intended and desired. By the processof application Serial No 844,438, the configuration of a molded articlepreform is substantially changed in the after-pressing operation. Thischange, which may conveniently be designated as a reforming of thearticle, is accomplished by having after-pressing dies of differentconfiguration or shape, in certain parts, than any of the other molds,dies or instrumentalities that were used to initially form the article.There is thus obtained a carton that may have the same general externalappearance to that of a previously known carton, but which will have theabove noted superior cushioning ability as a result of the forming andreforming.

In addition, it will be seen that where it is desired to modify, withincertain limits, the configuration of an article that is in production,it is only necessary with the present process to make new pressing diesandto install them only in that part of the apparatus that is used forafter-pressing, and it is not necessary to make and install new moldsand dies, throughout and to halt the apparatus until the new molds anddies can be installed. As a consequence, a four-week conversion time isreducible to less than a half of a day, with attendant saving ofproduction time and overhead and other expense.

Modiiication of the configuration of an egg carton finds one applicationin the manufacture of egg cartons of a size to hold very small eggsknown as the pullet size.

Pullet eggs are laid by new layers, and the season is generally heavierin July and August, although with the recently adopted practicerofrotating flocks, seasonal increases in pullet eggs are less pronouncedthan formerly.

In order to make pullet size molded pulp egg cartons, it would have beennecessary to produce complete sets of dies and forms for the entireproduction machinery. This would take about nine months, and :thusrequire con- -siderable advance planning. The new size dies would besubstituted during a four-week changeover period, and then after a shortrun was made, a second changeover period would be required to changeback to the original dies and forms. These changeover periods would havenecessitated the machine shut down for excessive periods with resultantloss of proits. As a result of these economic limitations, production ofthe pullet carton was precluded.

Further, it has lbeen found that for eggs of approximately the samediameter, some are longer, measured from the point of maximum girth,than others, and some of these longer eggs will come into contact withthe bottom of the egg cell.

Efforts have been made in the past to support the egg by holes or thinwafer-like sections, but the hole has been found to have a hard edge andthus to give rise to high local pressures on the egg, with resultantbreakage, and the control of quality limits of the thin sections hasproven diicult, so that there has not been provided heretofore anentirely satisfactory construction of egg carton cell bottom.

Modification of the coniiguration of an egg carton finds anotherapplication in the manufacture of egg cartons having a cellular bottomsection and a cover section with a planar top and posts to support theplanar top of the cover section.

While cellular bottom sections with posts between the cells have beenprovided, and while `it has been suggested that one or more of theseposts could be high enough to contact with the underside of the top ofthe cover section, in practice this latter constructionhas not beenadopted because those skilled in the art have considered it impossibleto achieve within the space limitations established by the egg packagingindustry. It may be mentioned parenthetically that the modification ofan existing carton construction by providing essentially a postresulting from an extension of the height of the Walls between the cellsat their existing angle results in a post with an extremely small orpointed top. This construction is not satisfactory because the post toptends to penetrate the cover top, rather than support it, andfurthermoreit is not practical to produce because. of complex construction.Alternatively, to provide a construction in which the angle of paper wasmodified to provide the necessary top area would result in aconstruction which would not nest nor give suflicient egg room.

An object of the present invention is to provide a novel molded pulp eggcarton that has a configuration which will protect the eggs fromaccidental breakage, and which has a unique structure Ito afford extremestructural strength. Y

Another object of the present invention is to provide a novel egg cartonin which a cellular tray includes hollow posts which will provide4columnar strength and including intermediate cushioning portions of aconsistency and thickness differing from those portions subject tovertical loading.

' A further object of the present invention is to provide a molded pulpegg carton that will reduce egg rattle and egg breakage and Whichaffords good nesting.

Another object of the present invention is the provision of an eggcarton that combines characteristics of high strength withcharacteristics of positively holding the egg in parts -thatrcushion theegg against shock.

Yet another object of the present invention is to provide an egg cartonproviding a soft and gentle support for longeggs at the bottom of thecell.

`Other objects andmany-.of the-attendant advantages ofthe presentinvention will become apparent upon con- 4 sideration of the followingspecification and accompanying drawings, wherein:

FIG. 1 Ishows schematically apparatus for producing the egg cartons ofthe invention;

FIG. 2 is a cross-sectional view, with parts in elevation, of a formingdie used for forming a preform used to produce the novel egg carton,with a preform thereon;

FIG. 3 is an elevation of a drying form;

FIG. 4 is a view showing, in stepped sections, pressing dies used toreform the carton;

-IG. 4a illustrates the relative dimensions and shapes of a portion ofthe preform posts before and after treatment in the pressing dies ofFIG. 4;

FIG. 4b is a cross sectional view showing the pressing dies of FIG. 4with a pressed and reformed preform therebetween;

FIG. 5 is a cr-oss-section, taken generally on line 5-5 of FIG. 6, ofthe novel egg carton after being reformed in the dies of FIG. 4 andshowing the article in a closed condition;

FIG. 6 is a fragmentary plan view of the open egg carton of FIG. 5;

FIG. 7 is a fragmentary elevational view of a single egg cell of thecarton shown in FIG. 6;

FIG. 8 is a cross-sectional view taken on the line 8 3 of FIG. 7;

FIG. 9 is a fragmentary plan View similar to FIG. 6 of the bottomsection of another embodiment of egg carton in accordance with thepresent invention;

FIG. 10 is a cross-sectional view taken on the line Iii-10 of FIG. 9;

FIG. 11 is a view similar to FIG. 10 and showing an egg in the cellthereof;

FIG. 12 is a fragmentary plan view similar to FIGS. 6 and 9 of thebottom section of still another embodiment of egg carton in accordancewith the present invention;

FIG. 13 is an elevational view of an egg cell of the bottom sectionshown in FIG. 12;

FIG. 14 is a cross-sectional view taken on the line .I4-14 of FIG. 13;

FIG. 15 is a cross-sectional view taken on the lines I5-15 of FIG. 12;

FIG. 16 is a view similar to FIG. 15 and showing an egg in the cellthereof;

FIG. 17 is a fragmentary plan view similar to FIGS. 6, 9 and 12 of thebottom section of a still further embodiment of egg carton in accordancewith the invention;

FIG. 18 is an elevational view of an egg cell of the bottom sectionshown in FIG. 17;

FIG. 19 is a fragmentary vertical section taken substantially on theline I9-19 of FIG. 17;

FIG. 20 is a cross-sectional view taken on the line Ztl-20 of FIG. 19;

FIG. 21 is a plan view of another embodiment of egg cell in accordancewith the present inventory;

FIG. 22 is a fragmentary plan view similar to FIGS. 6, 9, 12 and 17 ofyet another egg carton made in accordance with the present invention andon a slightly reduced scale;

FIG. 23 is a cross-sectional view taken on the line 23-23 of FIG. 22;

FIG. 24 is a cross-sectional View taken on the line 24-24 of FIG. 22;

FIG. 25 is a plan View of an egg flat incorporating the novel cellconstruction of the present invention; and

FIG. 26 is a cross-sectional view of the egg flat of FIG. 275, andshowing a cover in place thereon.

Referring now to the drawings, wherein like reference characters areused to designate like or corresponding parts throughout the severalviews, there is shown in FIG. l a preferred apparatus for producing thecarton of the invention, and there may be seen therein a moldingapparatus generally designated 20, this molding apparatus comprising inknown manner a molding wheel 21 having on the periphery thereof aplurality of forming dies 22. A tank 23 containing a pulp slurry ispositioned beneath the wheel 2l so that the forming dies 22'will beimmersed in the slurry as the wheel 21 revolves. In known fashion, whenthe die 22 is immersed in the slurrT suction will be applied to theinner side thereof to suck the `slurry through the mold 22 so that thepulp fibers lodge on the outer surface of the mold, which is usually aline mesh screen, and form a preform.

When the preform has been formed on the forming die 22, it leaves theslurry and at this stage contains a great amount of water. The wetpreform A is removed from the die 22 and transferred to a drying form 26that is carried by a conveyor 27. The conveyor 27 extends through adrying apparatus, preferably a drying oven 28. After traversing the oven28, the preform A is placed between pressing and reforming dies.

The pressing and reforming dies may be mounted as shown in FIG. 1 in apress 30 which carries mutually reciprocable mating dies 32 and '33. Thepreform A is removed from the drying form 26, and at this stage, it willbe understood that the preform A is formed and dried and that it usuallyhas at this stage of its manufacturer a small amount of warpage. Thepreform is transferred by known means to the press 30, and there is theneffected a reciprocable movement of one or both of the dies 32'and 33 tocause them to come together to press and reform or reshape the preform Abetween them. The preform after being dried is relatively rigid andbrittle and the reforming and reshaping provides a soft finish to thecarton, provide cushioning portions and structure aording increasedprotection for the eggs without radically affecting the strength of thecarton.

The die 22, shown best in FlG. 2, molds or forms the article A as abovestated; article A is, in the example shown, an egg carton having abottom section with egg receiving cells that are generally concave withan upstanding button on the cell bottom, as is well known; article Auniquely has posts 34 of sufficient height to engage the underside ofthe top of the cover when the carton is closed. The drying form 26,shown in FIG. 3, is of the same configuration as the die 22, and ispreferably a male form, as shown.

The pressing and forming dies 32 and 33, shown in FIG. 4, have portionsthereon which reform or reshape several parts of the carton bottomsection. The female die 32 has an upstanding post 34h that appears to besimilar to the post 34a of the die 22. Each post '34b has four sides,each of which conforms to the surface of an inclined cylinder, two suchsides being :shown in FIG. 4. However, the angle to the vertical of thesides of'post 34a of die 22 is less than the angle to the vertical ofthe sides of post 34th of the female pressing die 32. In practice, thisdifference is in the order of 2%.". The height of post Sfib is the sameas the height of post 34a, but the extent or area of the top of post 34ais greater than that of post 34h.

The male die y33 has a generally corresponding recess 34C, made up offour inclined sides which conform to the surface of cylinders; the sidesof recess 34e have, however, protruding generally elliptical blistersSlf which have their greatest outward extension at the approximatemidpoint thereof and -a-re each regularly curved therefrom. Thelblisters are in registry with corresponding areas of the article orcarton preform A of reduced thickness relative to the normal Vthicknessof the preform A.

As a result of the differences in the configuration of the forming dieand the pressing dies, during the pressing of the egg carton A, thewalls and top of the post are reformed; the pulp of the topvis crowdedtogether towards the center, but the relative height of the top of thepost is unchanged. This is shown in ElG. 4a, the dashed linesillustrating the size and shape of the CII post 34 of the article Aafter it is formed and dried, and the full lines illustrating the sizeand shape of the post 3 4 after it is reformed in the dies 32 and 33.The Walls of the posts are reformed by having the angle thereof changedso as to be less steep, this also appearing in FrG. 4a. By crowding thepreform pulp inwardly, the posts of the article are strengthened, andanyinadvertent flaws are eliminated, -i.e., if the posts are formedexcessively thin on the suction die, the crowded-in liber willcompensate for such imperfections.

The areas of carton A registering with the blisters 34j are alsoreformed, due to the relative shapes of the forming die 22 and lthepressing dies 32 and 33, particularly pressing die 33.

While the egg cells of the article A, as molded on die 22, are generallyconca-ve with rounded and llat portions as shown in the patent to CoxNo. 2,771,233, issued November 20, 1956, these cells are also reformedin the dies 32 and 33. In the female pressing and forming die 32flute-like protrusions 3617 are provided on the wall of the egg cellcavity thereof; these protrusions Sb are of a generally elongated teardrop shape having downwardly tapering tails. A shallow dent 36d ofpreferably circular configuration, is located `in the protrusion Seb,adjacent the upper end or head thereof. A corresponding yflute-likeindentation 36C is provided on the mating pyramidal male part of the die33, there being a bulge 36e at the upper end thereof. Pressing die 32also has an annular protrusion 37b on the bottom of the cavity thereof,and the male die 33 has a protrustion 37C (see FIG. 4b) on the bottom ofthe mating pyramidal male part, protrusion 37e being surrounded -by agroove 38.

In FIG. 4b there is shown a cross-sectional view, taken diagonallythrough an egg cell, and showing the article A being pressed andreformed in the pressing dies 32 and 33. The blister 35i-f is seenpressing and reforming a side of a post 34, the post 34 being thinnerthan normal where it is in registry with blister 341. This thinness isdue in part to the fact that this blister area was initially formedthinner on the preform and in part to the fact that the blister area islater pressed thinner between the blister V3I-if and the underlying partof the post 34h of die 32.

The 4blister' forming areas on the preform are formed thinner due toblanking-out elements (not shown) disposed at corresponding portions ofthe forarninous forming die whereby the pulp liber of the slurry is notsucked through the die :but tends to build over this area. However, theportions of :the hollow post extending from the base to the top thereofare of normal thickness Vduring formation of the preform and theconcentration of material is increased thereat during inward reformingas mentioned above. This in effec-t increases the columnar strength ofthe posts. Y

The annular protrusion 37b of pressing die 32 cooperates with theprotrusion 37C and groove 38 of pressing die 33, and the protrusion 35hand dent 36d cooperate with the flute-like indentation 36C and bulge36e, respectively.

The resulting article A as shown in F-G. 5 is, of course, the originalpreform A that was formed on the die 2-2, but has been reformed in partto have flutes 36 that extend into the egg cells of the article A, theflutes 36 having flattened upper ends 36'. Y button that was anupstanding protrusion on the bottom of the egg cell of Article A hasbeen reformed into a -thin wafer 39 having a surrounding pillow 39. Itwill be understood that the position and dimension of wafer .3-9 withrespect to the cell bottom, either higher, lower, thicker or thinnerthan that shown in FIG. 5, depends upon the existence and height of theprotrusion 37b and 37C on the dies 32 and 3-3. Thus, the wafer 39 mayappear other than as shown in FIG. 5. The posts 34 extend upwardly intoengagement withthe underside of planar top 35 of the integral coversection of carton A.

The molded pulp in the characteristics of that part of the articlethat'has been reformed. Thus it is to be understood that the vreformingof the parts of the article that become the flute-like protrusion 36 andwafer 39 shown in FIG. 5 serves to distunb the entire body of fiberstherein and the bond between the fibers. As to the flute-likeprotrusions 36, the carton Abody portion as initially formed wasconcave, and is reformed to a convex configuration that is considerablysofter and more yielding than the remaining nonreformed part of thearticle or carton A; i.e., the curvature is in a sense reversed. Thus,the article or carton A retains its general over-all strength but isprovided with finte-like protrusions 36 that possess completelydifferent characteristics from the other (non-reformed) parts of thecarton in that they -will yield more readily under load. The reformingof an article is great enough in certain instances to cause the reformedpart of the article to go to a point of opposite image; the originallyformed article may, for example, have a part that is concave a certainamount, and that is convex a like amount after reforming.

The wafer 39 and pillows 39 are also soft and yielding, and serve tocushion any long eggs that come into Contact with them, and thisformation will prevent leakage in the event of breakage.

Although the apparatus shown is the preferred apparatus for carrying outthe process, it will be understood that other apparatus may also be usedand that, in general, any apparatus that first forms an article and thenreforms it after it has dried, preferably, is suitable. For example, theprocess may be carried out by an apparatus in which the pulp is firstmolded into a sheet, and then the article is initially formed from thesheet; thereafter, the article may be reformed in accordance with `theabove teachings. Other apparatus that are suitable for carrying out theprocess of the invention will be apparent tothose skilled in the art,only one of the apparatus having been shown in the drawings.

Referring now to FIG. 6, there may be seen therein a plan view of thecarton shown in section in FIG. 5. The egg carton bottom section 40 isan egg receiving section having egg receiving cells 41, each of thecells 41 having a square bottom 42, from the sides of which the lowerwall portions 43 incline upwardly and outwardly at a predetermined angleto the vertical, thereby providing a generally polygonal lower portionof the cell. The polygonal lower wall portions 43 merge upwardly withrounded, generally conical, upper cell portions 44, and these upper cellportions 44 are at a lesser angle to the vertical than the lowerportions 43. The cell as thus described is known in the art, and isfully described in Patent No. 2,771,233, which issued to J. W. Cox onNovember 20, 1956. From each corner of the base 42 there extendsupwardly, and at an angle that is preferably but may be within the rangeof 10-15, the reformed convex utes 36. Flutes 36 have flattened upperends 36 to provide a cell having more room for the egg than would be thecase otherwise. In the bottom 42 there are the reformed wafers 39 andpillows 39.

FIG. 7 shows the appearance of an egg cell 41 from the outside thereof,and there may be seen the reverse, or concave, side of the flutes 36, aswell as` the flattened upper ends 36' thereof, the flat lower wallportions 43 Y and the conical upper cell portions 44.V

FIG. 8 shows the thin and yielding egg-contacting area 34' in the post34; the posts 34 in the regions on either side of the` area 34' beingrelatively thick and thus hav- ,the several walls diverge fromeachother.

ing a high strength to sustain vertical load or shock to the posts. Theposts 34 are therefore strong at the four regions where the sides of thepost 34 join each other, and consequently have good columnar strength.There may also be seen in FIG. 8 the shape of the flutes36 as well asthe flattened end 36 of one flute 36. In this embodiment, it will benoted that the elongated blisterformed areas 34 extend above and belowthe upper margin of the carton bottom section; see FIGS. 5 and 7.

The egg carton shown in FIG. 9 is generally similar to that shown inFIGS. 5 and 6, with the exception that there is not provided in thisembodiment the posts 34 Ithat contact the underside of the cover of thecarton. Instead, the posts are of normal height, i.e., they extend onlyas high as the highest part of the remainder of the bottom section.Thus, the carton of FIG. 9 more closely resembles that carton which isdisclosed in Cox Patent No. 2,771,233. The carton of FIG. 9, as will beapparent, is one which is reformed from a carton that s molded inaccordance with the Cox patent, and therefore does not require theproduction of or changeover to new molding dies in a plant having suchdies for the production of the carton of the Cox patent.

The carton of FIG. 9V has a bottom egg receiving section with egg cells41 that are the same as egg cells 41 of the bottom section shown in FIG.6. Thus, there is shown in FIG. 9 the bottom 42 with wafer 39 and pillow39', the lower wall portions 43 and the upper cell portions 44.

The flutes 36 are of teardrop shape at their upper ends to facilitatethe reforming of the material and have a relatively large radius. Theradius is important from considerations of flexibility, flexing of thematerial and the convergence of the flutes at the cell junctures.

In FIG. 10 there may be seen the egg cell 41 having the two flutes 36therein in full line position, the portions that formed the flutes 36before the reforming of the carton bottom section 45 being shown indotted lines.

Eggs placed in an egg cell 41 will lodge upon the flutes 36 therein, andas shown in FIG. 11 will deflect and depress the reformed flute 36because of the softness and cushioning ability thereof. The cushioningability of the reformed flute 36 is such that an egg may be safelydropped into the cell 41, as is done in automatic egg carton fillingmachinery, without danger of egg breakage. With the reformed flute, eachcell acts independently, so that a heavier egg in one cell will causethe reformed utes thereof to deflect without having any effect on theeggs in adjacent cells or the adjacent cells themselves.

In the copending application of Henry A. Lord and Harold S. Crane,Serial No. 669,362, filed July 1, 1957, which matured into United StatesLetters Patent No. 2,924,368 on February 9, 1963, there is described anegg carton having egg receiving cells that are generally triangular, ortrapezoidal, and such a carton has been shown in FIG. 12, reformed inaccordance with the present invention. Thus, there may be seen in FIG.12 a lower section of an egg carton, section 50 having a plurality ofcells 51 each of which includes a horizontal base 52 that issubstantially in the shape of an equilateral triangle, or regulartrapezoid. Extending upwardly from each of the three edges of cell base52 of each cell is a cell wall, there being therefore three walls 53, 54and 55. Each of the walls 53, 54 and 55 tapers in width perimetricallyof the cell in extending upwardly towards the top of the carton bottomsection. Also, each of the cell walls or lowermost portions inclinesupwardly and outwardly from the base 52, so that Above the Walls 53, 54and 55` there are upper wall portions 53A, 54A and 55A that extendupwardly from the top of their respective lower Walls and at a lesserangle to the vertidal. Extending between the Walls above described andasshown on the drawing, there are auxiliary walls 56, 57 and 53, andthese auxiliary walls are of substantially the same angle of inclinationas the upper Wall portions 53A, 54A and 55A and extend upwardly from theapices of the triangular base 52, increasing in width from said apices.

Flutes 53B, 54B and 55B are reformed from the corresponding lower andupper walls 53, 53A, 54, 54A, and 55, 55A.

The appearance of typical flute 54B is shown in FIG. 13, and theprotrusion of the utes 53B, 54B and 55B into the cell` 51 is clearlyshown in FIG. 14. FIG. v15 shows in dotted lines the position of thewalls 53, 53A

and 54, 54A after the carton 50 is initially formed and shows in fulllines the reformed utes 53B and 54B, in accordance with the invention.

In FIG. 16 there may be seen cell 51 having the reformed flutes 53B and54B, and it may be clearly seen that these reformed flutes havedeflected in order to accommodate and receive in a cushioning manner theegg therein.

In FIG. 17 there is shown a lower section 60 of an egg carton having aplurality of cells 61 each of which includes a horizontal base 62 thatis substantially in the shape of a trapezoid. Extending upwardly fromeach of the four edges of cell base 62 of each cell is a cell wall, thefour walls being designated 63, 64, 65, 66. As in the carton 50 of FIGS.12, 13 and 14, each of these walls extends upwardly toward the top ofthe carton bottom section, and as in carton 50 each of the cell wallsinclines upwardly and outwardly from the base 62 and diverges from eachother wall.

Reformed flutes 67, 63, 69 and 70 may be seen in the upper parts of thecells 61. In this embodiment, no ute is adjacent the hinge 71, asresults with the placement shown in FIGS. 12, 13 and 14.

FIG. 18 illustrates the appearance of the cell 61, in exteriorelevation, and showing the reformed flutes 68 and 69, which are thoseflutes that are closest to the outer margins of the carton bottomsection 60. FIG. 19 shows the reformed liutes 67 and 70' that are closerto the interior of bottom section 60, these two views showing therelative spacing of these pairs of reformed flutes. As is best shown inFIG. 19, the utes 67 and 70, which are in the walls of the posts ofbottom section 60, extend from adjacent the tops of the posts andterminate well above the bottom 62. These liutes 67 and 70 are thusrelatively short.

In FIG. 20, there may be seen the convex reformed utes 67, 68, 69 and70, and the straight walls 63, 64, 65 and 66 of the cell 61therebetween.

FIG. 21 shows a cell S0 that is generally similar to the cell 61, buthas only two liutes 87 and 90 therein, corresponding to the utes 67 and70 of the cell 61. This is a simpler cell which provides suitablecushioning support for the eggs.

In FIGS. 22 and 23 there is shown a carton bottom section 100 similar tothe carton bottom section 60 of FIG. 17, in that the cells 101 of thiscarton are of the generally triangular shape of the cells 61. Thus, thecells 101 may be seen to comprise a generally triangular bottom 102 withthe three main diverging and inclined walls 103, 104 and 105 risingtherefrom. The walls 104 are parts of a reformed post 106 which has aheight sufiicient to Contact and support the underside of the cartoncover, the height of post 106 being clearly shown in FIG. 23.

The underside of walls 104 and 105 of the posts 106 are thin in the areaindicated at 107. The thinned areas 107 are of generally tear drop shapeand are positioned laterally intermediately of the walls 104 and 105.They extend from near the top of walls 104 and 105 to adjacent the levelof the cell bottoms 102, and therefore are engaged by eggs placed in thecells. Because of the thinness of the areas 107, the walls 104 and 105will deflect under the weight of an egg, and thus will yielding- Cal 10ly cushion the egg. These areas are similar to the thinned areas 34 ofthe carton A, shown in FIGS. 5 to 9.

The triangular cell 101 may be utilized in an egg at for holdingthirty-six eggs, as is shown in FIG. 25, wherein there may be seen thecells 101 each having a bottom 102 and the walls 103, 104 and 105, thelatter forming the posts 106. There are three rows of posts 106, and'inaddition there are two rows of posts 108, one row of posts 108 lyingbetween each two rows of the posts 106.

The walls 104 and 10S of the posts 106 of the egg flat may also haveVthe thinned areas 107, as isV shown in FIG. 26, where there is alsoshown the posts 106 and 108. A cover 109 having a planar top 110 anddepending side walls 11,1 may be positioned on the egg tray, to protecteggs therein. The posts 106 and 108 will engage with and support theunderside of the top 110 of the cover 109.

The egg liat of FIGS. 25 and 26 may be divided into groups of cells witheach group containing only a few cells. Thus, each group may contain onedozen eggs, or a half-dozen eggs. Where a dozen eggs is tobe sold, theegg flat may be cut along a line of posts 108, and the cover 109 cutcorrespondingly.

There has been provided a greatly improved molded puip article,particularly a molded pulp egg carton. In accordance with the apparatusand process the preform is irst or initially formed and lthen a part ofthe article is reformed and reshaped, and this part obtains thereby asoftness and resiliency that it did not initially possess and which isnot possessed by articles or cartons that are initially formed in thesame conguration as the reformed article or carton hereof.

There is provided superior egg cartons that have reformed flutesextending or protruding into the cell space to receive an egg in asecure manner and yet which cushion the egg so as to reduce egg rattleand egg breakage. Further, by the process of the present invention, itis possible for the first time to manufacture molded pulp egg cartons inwhich a post extends upwardly from a bottom section to engage a planartop of a cover section.

It will be obvious to those skilled in the art that various changes maybe made Without departing from the spirit of the invention and thereforethe invention is not limited to what is shown in the drawings anddescribed in the speciiication but only as indicated in the appendedclaims.

What is claimed is:

1. In a one-piece molded container comprising a cellular bottom trayincluding an upper peripheral margin and a plurality of individual cellgroups about a hollow, vertically extending post, said post terminatingabove the upper peripheral margin of said bottom tray, at least one ofsaid cells comprising a plurality of vertically diverging walls spacedabout a base, the hollow post having a side Vwall portion forming one ofsaid diverging wall portions,

and a dished cover hingedly connected to and including a lowerperipheral margin engageable on the upper peripheral margin of saidbottom tray, said vertically extending post including an upper terminalend portion engageable with an inner surface portion of said dishedcover for absorbing vertical compressive forces transmitted to saidcover when said container is closed; the improvement comprising avertically disposed cushioning-area portion disposed intermediately ofsaid post side wall portion between the upper terminal end thereof andsaid base and disposed in intersecting relationship with respect to aplane passing through the upper peripheral margin of said bottom tray,said cushioning-area portion being transversely thinner and of adifferent consistency than adjacent anking portions of said post sidewall portion and having independent exibility with respect to saidadjacent portions of said post, said adjacent portions of said postcomprising a concentration of material from the top thereof flankingsaid cushioning-area portion down to said base for providing increasedcolumnar strength to 1.1 said post and providing a stable base for theindependent flexibility of said cushioning-area portion.

2. The structure of claim 1 in which said diverging Wall portions ofsaid cell have a generally concave horizontal cross section when lookinginto said cell, said cushioningarea portion of said post side Wallportion having a conveX, horizontal cross section projecting into saidcell out of said adjacent portions of said post side wall portion.

3. The structure as claimed in claim 1 in which said verticallyextending post has a truncated, pyramidal shape including foursubstantially planar sides, each of said planar `sides including one ofsaid intermediate cushioning-area portions, the portions of said postexclusive of said cushioning-area portions comprising said concentrationof pressed material from the terminal end portion of said post down tosaid base and at the intersections of said adjacent planar sides.

4. The structure as claimed in claim 2 in which said convex horizontalcross section on said post side Wall p0rtion comprises a generallyelliptical, vertically disposed geometric shape and being independentlyflexible With respect to said adjacent portions of said post side Wallpor- Vtions'and being yieldable when engaged by an article deposited inthe cell.

References Cited by the Examiner UNITED STATES PATENTS FRANKLIN T.GARRETT, Primary Examiner.

EARLE I. DRUMMOND, Examiner.

1. IN A ONE-PIECE MOLDED CONTAINER COMPRISING A CELLULAR BOTTOM TRAYINCLUDING AN UPPER PERIPHERAL MARGIN AND A PLURALITY OF INDIVIDUAL CELLGROUPS ABOUT A HOLLOW, VERTICALLY EXTENDING POST, SAID POST TERMINATINGABOVE THE UPPER PERIPHERAL MARGIN OF SAID BOTTOM TRAY, AT LEAST ONE OFSAID CELLS COMPRISING A PLURALITY OF VERTICALLY DIVERGING WALLS SPACEDABOUT A BASE, THE HOLLOW POST HAVING A SIDE WALL PORTION FORMING ONE OFSAID DIVERGING WALL PORTIONS, AND A DISHED COVER HINGEDLY CONNECTED TOAND INCLUDING A LOWER PERIPHERAL MARGIN ENGAGEABLE ON THE UPPERPERIPHERAL MARGIN OF SAID BOTTOM TRAY, SAID VERTICALLY EXTENDING POSTINCLUDING AN UPPER TERMINAL END PORTION ENGAGEABLE WITH AN INNER SURFACEPORTION OF SAID DISHED COVER FOR ABSORBING VERTICAL COMPRESSIVE FORCESTRANSMITTED TO SAID COVER WHEN SAID CONTAINER IS CLOSED; THE IMPROVEMENTCOMPRISING A VERTICALLY DISPOSED CUSHIONING-AREA PORTION DISPOSEDINTERMEDIATELY OF SAID POST SIDE WALL PORTION BETWEEN THE UPPER TERMINALEND THEREOF AND SAID BASE AND DISPOSED IN THE INTERSECTING RELATIONSHIPWITH RESPECT TO A PLANE PASSING THROUGH THE UPPER PERIPHERAL MARGIN OFSAID BOTTOM TRAY, SAID CUSHIONING-AREA PORTION BEING TRANSVERSELYTHINNER AND OF A DIFFERENT CONSISTENCY THAN ADJACENT FLANKING PORTIONSOF SAID POST SIDE WALL PORTION AND HAVING INDEPENDENT FLEXIBILITY WITHRESPECT TO SAID ADJACENT PORTIONS OF SAID POST, SAID ADJACENT PORTIONSOF SAID POST COMPRISING A CONCENTRATION OF MATERIAL FROM THE TOP,THEREOF FLANKING SAID CUSHIONING-AREA PORTION DOWN TO SAID BASE FORPROVIDING INCREASED COLUMNAR STRENGTH TO SAID POST AND PROVIDING ASTABLE BASE FOR THE INDEPENDENT FLEXIBILITY OF SAID CUSHIONING-AREAPORTION.